The overall goal of this research project is to increase our understanding of the physiological mechanisms underlying neuroendocrine regulation of pituitary function in primates. Our research goals for the coming year are, first, to investigate further the role of testicular hormones in regulating LH pulse amplitude and frequency in the male monkey, and second, to investigate the possible role of insulin and other metabolic hormones in sexual maturation in the monkey. A better understanding of these mechanisms is of great physiological interest and may offer new insights into understanding the physiological basis for the onset of puberty and the control of gonadotropin secretion in human beings. Elucidation of the mechanisms of these physiological processes could allow better management of disorders of pubertal development (e.g., delayed or precocious) or adult male reproductive function (e.g., infertility).